X-ray diagnosis apparatus and method for obtaining an X-ray image

ABSTRACT

A method for obtaining an X-ray image for an X-ray diagnosis apparatus including plurality of imaging systems, including: collecting first scatter data using a first X-ray detector after an X-ray is irradiated from a first X-ray tube in a first imaging system; collecting second scatter data using a second X-ray detector after an X-ray is irradiated from a second X-ray tube in a second imaging system; collecting first image data including a scatter component using X-ray detectors after an X-ray is irradiated from a third X-ray tube in the first imaging system; collecting second image data including a scatter component using X-ray detectors after an X-ray is irradiated from a fourth X-ray tube in the second imaging system; and obtaining X-ray images for the first and second imaging systems by subtracting the first and second scatter data from the first and second image data including a scatter component, respectively.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is based upon and claims the benefit of priority fromprior Japanese Patent Application No. 2003-35569 filed on Feb. 13, 2003,the entire contents of which are incorporated herein by reference.

FIELD OF THE INVENTION

The present invention relates generally to an X-ray diagnosis apparatusincluding a plurality of imaging systems and a method for obtaining anX-ray image.

BACKGROUND OF THE INVENTION

As shown in FIG. 1, a biplane X-ray imaging apparatus (mainly developedfor cardio vascular inspection) has two imaging systems to performimaging from two directions simultaneously. One imaging system has afront imaging system 1 including an X-ray tube 3 and an X-ray detector 4for obtaining an image of a patient on a plate of a bed from a frontside. The other imaging system has a lateral imaging system 2 includingan X-ray tube 5 and an X-ray detector 6 for imaging the patient from alateral-side.

In the biplane X-ray imaging apparatus, the X-rays generated from theX-ray tube 3 of the front imaging system 1 pass through the patient P todirectly enter the X-ray detector 4, and also reflect to enter the X-raydetector 6 as scattered X-rays. Similarly, the X-rays generated from theX-ray tube 5 of the front imaging system 2 pass through the patient P toenter the X-ray detector 6, and also reflect inside the patient P toenter the X-ray detector 4 as scattered X-rays.

Therefore, in an imaging sequence, as shown in FIG. 2 and FIGS. 3A-3D,when the X-rays are generated from the X-ray tube 3 of the front imagingsystem 1 and a signal is read out from the X-ray detector 4 of the frontimaging system 1, a signal is read out from the X-ray detector 6 of thelateral imaging system 2 to remove an electric charge generated by thescattered X-rays. After the signal is read out, when the X-rays aregenerated by the X-ray tube 5 of the lateral imaging system 2 and asignal is read from the X-ray detector 6 of the lateral imaging system2, a signal is read out from the X-ray detector 4 of the front imagingsystem 1 to remove an electric charge generated by the scattered X-rays.

Although the influence of each of the scattered X-rays between the frontimaging system 1 and lateral imaging system 2 can be removed by theabove-mentioned method, the imaging is performed by a double cycle ofthe minimum cycle of each X-ray detector. That is, an effective framerate (the number of the frames per unit time) decreases to half of themaximum speed.

As a non-limiting example, it is conceptually desirable that a cardiacimaging is simultaneously performed from the front and lateral sides.However, since the imaging of the front imaging system 1 and the lateralimaging system 2 are performed in turn at a fixed cycle to avoid theinfluence of the scattered X-rays, the time gap between the front andlateral sides still remains.

In addition, a biplane X-ray diagnosis apparatus is described inJapanese Patent Publication (Kokai) No. 2000-102529.

SUMMARY OF THE INVENTION

Objects of the present invention include: to reduce the influence ofscattered X-rays, to improve the frame rate, and to reduce the time gapbetween front imaging and lateral imaging.

According to one aspect of the invention, method for obtaining an X-rayimage for an X-ray diagnosis apparatus including plurality of imagingsystems is provided, the method including: collecting first scatter datausing a first X-ray detector after at least one X-ray is irradiated froma first X-ray tube in a first imaging system; collecting second scatterdata using a second X-ray detector after at least one X-ray isirradiated from a second X-ray tube in a second imaging system;collecting first image data including a scatter component using aplurality of X-ray detectors after at least one X-ray is irradiated froma third X-ray tube in the first imaging system; collecting second imagedata including a scatter component using a plurality of X-ray detectorsafter at least one X-ray is irradiated from a fourth X-ray tube in thesecond imaging system; and obtaining X-ray images for the first and thesecond imaging systems by subtracting the first and second scatter datafrom the first and second image data including a scatter component,respectively.

According to another aspect of the invention, a method for obtaining anX-ray image using an X-ray diagnosis apparatus including a first imagingsystem including a first X-ray tube and a first X-ray detector and asecond imaging system including a second X-ray tube and a second X-raydetector is provided, the method including: collecting scatter datausing the second X-ray detector after at least one X-ray is irradiatedfrom the first X-ray tube; collecting scatter data using the first X-raydetector after at least one X-ray is irradiated from the second X-raytube and subsequently collecting the scatter data using the second X-raydetector; collecting, substantially simultaneously, image data includinga scatter component using the first and the second X-ray detectors; andobtaining X-ray images imaged using the first imaging system and thesecond imaging system by subtracting the scatter data collected by thefirst and second X-ray detectors from the image data including thescatter component collected by the first and second X-ray detectors,wherein a collection time of the scatter data is shorter than acollection time of the image data including the scatter component.

Another non-limiting aspect of the invention includes a method forobtaining an X-ray image using an X-ray diagnosis apparatus including afirst imaging system including a first X-ray tube and a first X-raydetector and a second imaging system including a second X-ray tube and asecond X-ray detector, the method including: collecting, substantiallysimultaneously, scatter data using the first and second X-ray detectorsafter at least one X-ray is irradiated from the first X-ray tube;collecting, substantially simultaneously, image data including a scattercomponent using the first and the second X-ray detectors after at leastone X-ray is irradiated from the second X-ray tube; and obtaining X-rayimages imaged using the first imaging system and the second imagingsystem by subtracting the scatter data collected by the first and secondX-ray detectors from the image data including the scatter componentcollected by the first and second X-ray detectors, wherein a collectiontime of the scatter data is shorter than a collection time of the imagedata including the scatter component.

Another non-limiting aspect of the invention includes a method forobtaining an X-ray image using an X-ray diagnosis apparatus including afirst imaging system including a first X-ray tube and a first X-raydetector and a second imaging system including a second X-ray tube and asecond X-ray detector, the method including: collecting, substantiallysimultaneously, first scatter data using the first and second X-raydetectors after at least one X-ray is irradiated from the first X-raytube; collecting second scatter data using the first X-ray detectorafter at least one X-ray is irradiated from the second X-ray tube andsubsequently collecting the second scatter data using the second X-raydetector, subsequently collecting, substantially simultaneously, imagedata including a scatter component using the first and second X-raydetectors; subtracting the second scatter data from the first scatterdata, thereby obtaining subtracted scatter data; obtaining an X-rayimage by subtracting the subtracted scatter data from the image dataincluding the scatter component collected by the first X-ray detector;and obtaining an X-ray image by subtracting the scatter data collectedby the second X-ray detector from the image data including the scattercomponent collected by the second X-ray detector, wherein a collectiontime of the scatter data is shorter than a collection time of the imagedata including the scatter component.

An X-ray diagnosis apparatus according to another aspect of theinvention includes: a plurality of X-ray tubes; and a plurality of X-raydetectors corresponding to respective X-ray tubes, wherein each of theplurality of X-ray detectors includes a first image data collectionfunction for collecting image data using a first number of detectionelements and a second image data collection function for collectingimage data by a second number of detection elements, the second numberbeing fewer than the first number.

Another aspect of the invention provides a method for obtaining X-rayimage by an X-ray diagnosis apparatus including a first X-ray tubeconfigured to irradiate X-rays in a first direction, a first X-raydetector corresponding to the first X-ray tube, a second X-ray tube forirradiating X-rays in a second direction different from the firstdirection, and a second X-ray detector corresponding to the second X-raytube, the method including: collecting first image data using the secondX-ray detector based on at least one X-ray irradiated from the firstX-ray tube; collecting second image data using the first X-ray detectorbased on at least one X-ray irradiated from the second X-ray tube;collecting third image data at a speed lower than a collecting speed ofthe second image data using the first X-ray detector based on the X-raysirradiated from the first and second X-ray tubes; collecting at a speedlower than a collecting speed of the first image data fourth image datausing the second X-ray detector, substantially simultaneously with thecollecting the third image data, based on the X-rays irradiated from thefirst and second X-ray tubes; removing a scatter component included inthe third image data using the second image data; and removing a scattercomponent included in the fourth image data using the first image data.

Another aspect of the invention provides a method for obtaining an X-rayimage using an X-ray diagnosis apparatus including a first X-ray tubeconfigured to irradiate X-rays in a first direction, a first X-raydetector corresponding to the first X-ray tube, a second X-ray tube forirradiating X-rays in a second direction different from the firstdirection, and a second X-ray detector corresponding to the second X-raytube, the method including: collecting first image data using the secondX-ray detector based on at least one X-ray irradiated from the firstX-ray tube; collecting second image data using the first X-ray detectorbased on the at least one X-ray irradiated from the first X-ray tube;collecting third image data using the first X-ray detector based onX-rays irradiated from the first and second X-ray tubes; collectingfourth image data using the second X-ray detector, substantiallysimultaneously to collecting the third image data, based on the X-raysirradiated from the first and second X-ray tubes; removing a scattercomponent included in the third image data using the second image data;and removing a scatter component included in the fourth image data usingthe first image data.

Another non-limiting aspect of the invention includes a method forobtaining an X-ray image using an X-ray diagnosis apparatus including afirst X-ray tube configured to irradiate X-rays in a first direction, afirst X-ray detector corresponding to the first X-ray tube, a secondX-ray tube configured to irradiate X-rays in a second directiondifferent from the first direction, and a second X-ray detectorcorresponding to the second X-ray tube, the method including:irradiating at least one X-ray from the first X-ray tube; collectingfirst image data using the second X-ray detector based on the at leastone X-ray irradiated from the first X-ray tube; irradiating at least oneX-ray from the second X-ray tube; collecting second image data using thesecond X-ray detector based on the X-rays irradiated from the first andsecond X-ray tubes at a lower speed than a collecting speed of the firstimage data; and removing a scatter component included in the secondimage data using the first image data.

Another aspect of the present invention includes an X-ray diagnosisapparatus, including: a first X-ray tube configured to irradiate X-raysin a first direction; a first X-ray detector corresponding to the firstX-ray tube; a second X-ray tube configured to irradiate X-rays in asecond direction different from the first direction; a second X-raydetector corresponding to the second X-ray tube; a controller configuredto control the second X-ray detector to collect first image data basedon at least one X-ray irradiated from the first X-ray tube, the firstX-ray detector to collect second image data based on at least one X-rayirradiated from the second X-ray tube, the first X-ray detector tocollect third image data based on the X-rays irradiated from the firstand second X-ray tubes at a lower speed than a collecting speed of thesecond image data, the second X-ray detector to collect fourth imagedata, substantially simultaneously to collecting the third image data,based on the X-rays irradiated from the first and second X-ray tubes ata lower speed than a collecting speed of the first image data; and animage processor configured to remove a scatter component included in thethird image data using the second image data and to remove a scattercomponent included in the fourth image data using the first image data.

Another non-limiting aspect of the present invention includes an X-raydiagnosis apparatus, including: a first X-ray tube configured toirradiate X-rays in a first direction; a first X-ray detectorcorresponding to the first X-ray tube; a second X-ray tube configured toirradiate X-rays in a second direction that is different from the firstdirection; a second X-ray detector corresponding to the second X-raytube; a controller configured to control the second X-ray detector tocollect first image data based on at least one X-ray irradiated from thefirst X-ray tube, the first X-ray detector to collect second image databased on at least one X-ray irradiated from the first X-ray tube, thefirst X-ray detector to collect third image data based on the X-raysirradiated from the first and second X-ray tubes, the second X-raydetector to collect fourth image data, substantially simultaneously tocollecting the third image data, based on the X-rays irradiated from thefirst and second X-ray tubes; and an image processor configured toremove a scatter component included in the third image data by using thesecond image data and to remove a scatter component included in thefourth image data using the first image data.

Another non-limiting aspect of the invention provides an X-ray diagnosisapparatus including: a first X-ray tube configured to irradiate X-raysin a first direction; a first X-ray detector corresponding to the firstX-ray tube; a second X-ray tube configured to irradiate X-rays in asecond direction different from the first direction; a second X-raydetector corresponding to the second X-ray tube; a controller configuredto control the first X-ray tube to irradiate at least one X-ray, thesecond X-ray detector to collect first image data based on the at leastone X-ray irradiated from the first X-ray tube, the second X-ray tube toirradiate at least one X-ray, and the second X-ray detector to collectsecond image data based on the X-rays irradiated from the first andsecond X-ray tubes at a lower speed than a collecting speed of the firstimage data; and an image processor configured to remove a scattercomponent included in the second image data using the first image data.

BRIEF DESCRIPTION OF THE DRAWINGS

A more complete appreciation of the invention and many of the attendantadvantages thereof will be readily obtained as the same becomes betterunderstood by reference to the following detailed description whenconsidered in connection with the accompanying drawings. In thedrawings:

FIG. 1 is an illustration for explaining scattered X-rays;

FIG. 2 is an illustration for explaining a conventional imagingsequence;

FIGS. 3A through 3D are illustrations for explaining scattered X-rays;

FIG. 4 is a block diagram of an X-ray diagnosis apparatus of anon-limiting embodiment;

FIG. 5 is an illustration for explaining an imaging sequence accordingto the embodiment;

FIGS. 6A through 6D are illustrations for explaining a scattered X-raysaccording to the embodiment;

FIG. 7 is an illustration for explaining an exemplary part of theimaging sequence of FIG. 5;

FIG. 8 is an illustration for explaining an example of a two-layer typeX-ray detector of FIG. 4;

FIG. 9 is an illustration for explaining another example of a two-layertype X-ray detector of FIG. 4;

FIG. 10 is an illustration for explaining another example of a two-layertype X-ray detector of FIG. 4;

FIG. 11 is an illustration for explaining another example of a two-layertype X-ray detector of FIG. 4;

FIG. 12 is an illustration for explaining an imaging sequence and animage processing of each format.

FIG. 13 is an illustration for explaining an example of a one-layer(independent signal line) type X-ray detector of FIG. 4;

FIG. 14 is an illustration for explaining an example of a one-layer(common signal line) type X-ray detector of FIG. 4;

FIG. 15 is an illustration for explaining another example of a one-layer(common signal line) type X-ray detector of FIG. 4;

FIG. 16 is an illustration for explaining an imaging sequence and animage processing of each format;

FIG. 17 is an illustration for explaining another imaging sequence andanother image processing of each format;

FIG. 18 is an illustration for explaining another imaging sequence andanother image processing of each format;

FIG. 19 is an illustration for explaining another imaging sequence andanother image processing of each format;

FIG. 20 is an illustration for explaining another imaging sequence andanother image processing of each format;

FIG. 21 is an illustration for explaining another imaging sequence andanother image processing of each format;

FIG. 22 is an illustration for explaining another imaging sequence andanother image processing of each format;

FIG. 23 is an illustration for explaining another imaging sequence andanother image-processing of each format; and

FIG. 24 is an illustration for explaining another imaging sequence andanother image processing of each format.

DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS OF THE INVENTION

With reference to the drawings, a non-limiting embodiment of a biplaneX-ray imaging method and a biplane X-ray imaging apparatus is explained.FIG. 4 shows a block diagram of the biplane X-ray imaging apparatus. Thebiplane X-ray imaging apparatus includes two or more X-ray imagingsystems, for example, a front imaging system (F), and a lateral imagingsystem (L). The front imaging system F has an X-ray tube 11 and an X-raydetector 12 positioned opposite the X-ray tube 11. A patient ispositioned between the X-ray tube 11 and the X-ray detector 12. Thelateral imaging system L has an X-ray tube 21 and an X-ray detector 22positioned opposite the X-ray tube 21. A patient is positioned betweenthe X-ray tube 21 and the X-ray detector 22.

The X-ray detectors 12 and 22 may be solid flat detectors including aplurality of detection elements (pixels) that change incident X-raysinto an electric charge directly or indirectly and are 2-dimensionallyarranged, for example. The X-ray tube 11 of the front imaging system isattached in one end of a C-arm located on the floor (not shown), and theX-ray detector 12 is attached in the other end of the C-arm. The X-raytube 21 of the lateral imaging system is attached in one end of an Ω-armhung from a ceiling (not shown), and the X-ray detector 22 is attachedin the other end of the Ω-arm. A supporting machine of the C-arm and asupporting machine of the Ω-arm are designed so that an imaging centeraxis which connects a detection center of the X-ray detector 12 to afocus of the X-ray tube 11 crosses an imaging center axis which connectsa detection center of the X-ray detector 22 to a focus of the X-ray tube21 at the so-called isocenter.

An F-side X-ray control unit 13 is connected to the X-ray tube 11 of thefront imaging system. The F-side X-ray control unit 13 applies a highvoltage between a cathode and a rotation anode of the X-ray tube 11.Moreover, the F-side X-ray control unit 13 supplies heating current to acathode filament of the X-ray tube 11. A heat electron emitted from theheated filament collides with a target of the rotation anode. Thereby,the X-rays are generated. An L-side X-ray control unit 23 is connectedto the X-ray tube 21 of the lateral imaging system. The L-side X-raycontrol unit 23 applies a high voltage between a cathode and a rotationanode of the X-ray tube 21. Moreover, the L-side X-ray control unit 23supplies heating current to the cathode filament of the X-ray tube 21.An F-side detector control unit 14 is connected to the X-ray detector 12of the front imaging system. The F-side detector control unit 14controls data read out from the F-side X-ray detector 12. An L-sidedetector control unit 24 is connected to the X-ray detector 22 of thelateral imaging system. The L-side detector control unit 24 controlsdata read out from the L-side X-ray detector 22.

A system controller 31 controls each operation of the F-side X-raycontrol unit 13, the F-side detector control unit 14, the L-side X-raycontrol unit 23, and the L-side detector control unit 24 to perform animaging operation, and controls a memory unit 33, an image-processingunit 35 and a display unit 37 according to the imaging operation.

An exemplary imaging sequence of the embodiment is shown in FIG. 5, FIG.6, and FIG. 7. The imaging sequence is divided into four terms. In term(1), the X-rays are generated from the F-side X-ray tube 11, and in thenext term (2), rough (low spatial resolution) image data is read fromthe X-ray detectors 12 and 22 of both the F and the L sides at highspeed. In term (3), the X-rays are generated from the L-side X-ray tube21, and in term (4), rough image data is almost simultaneously read fromthe X-ray detectors 12 and 22 of both F and L sides at high speed, andfine (high spatial resolution) image data is almost simultaneously readfrom the X-ray detectors 12 and 22 of both F and L sides at low speed.

In the non-limiting embodiment, three kinds of image data are acquiredin the F-side imaging system and the L-side imaging system,respectively. The three kinds image data contain different signalcomponents and different scatter components, respectively. When imageprocessing is performed on at least two types of image data among thethree types of image data, the scatter components of the F-side andL-side imaging systems are removed, and fine image data that mainlyincludes the signal components is obtained.

Thus, in term (4) the F-side and L-side data read out is performed inparallel. Therefore, cycle time can be shortened and a frame rate can bereduced in comparison with serial data read out from the L and F-sides.Moreover, although it is useful to read out the scatter component toremove the scatter component from each image, in the embodiment, theinfluence caused by the read out operation of the scatter component tothe cycle time can be reduced by reading out the scatter component atlow resolution and at high speed (short time), considering that spatialfrequency of the scatter component is low. Furthermore, by reading outthe scatter component at low resolution and at high speed, term (2) canbe shortened and a gap for imaging time between the F-side and theL-side can be shortened.

The above-mentioned imaging sequence is an exemplary imaging sequence,and there are many variations by combining a read out format of theX-ray detector, a structure of the X-ray detector, and image-processingformat. Read out formats include an electric charge read out format anda voltage read out format. Each format can be applied in the embodiment.Since the electric charge in a pixel capacitor remains after the data isread out in the voltage read out format, a flush operation is necessaryto reset the pixel capacitor. Options for timing of the flush operationinclude: a flush every read out type and a flush every frame. Structuresof the X-ray detector include: a two-layer type, a partial read out type(a single layer, independent signal line), and a partial read out type(a single layer, common signal line), for example. Moreover, imageprocessing formats include: spatial correction, reuse reconstruction,low resolution conversion, and modified algorithm low resolutionconversion. There are many possible variations of the imaging sequenceby combining the above-mentioned options, as well as variations thatwill be apparent to one of ordinary skill in the art. Some non-limitingcombinations include the following:

(1-1) Electric charge read out format+Two layer type,

(1-2) Electric charge read out format+Partial read out type (a singlelayer, independent signal line)+Spatial correction,

(1-3) Electric charge read out format+Partial read out type (a singlelayer, common signal line)+Spatial correction,

(2-1) Electric charge read out format+Partial read out type (a singlelayer, independent signal line)+Reuse reconstruction,

(2-2) Electric charge read out format+Partial read out type (a singlelayer, common signal line)+Reuse reconstruction,

(3-1) Voltage read out format+Flush every read out type+Two layer type,

(3-2) Voltage read out format+Flush every read out type+Partial read outtype (a single layer, independent signal line)+Spatial correction,

(3-3) Voltage read out format+Flush every read out type+Partial read outtype (a single layer, common signal line)+Spatial correction,

(4-1) Voltage read out format+Flush every read out type+Partial read outtype (a single layer, independent signal line)+Reuse reconstruction,

(4-2) Voltage read out format+Flush every read out type+Partial read outtype (a single layer, common signal line)+Reuse reconstruction,

(5-1) Voltage read out format+Flush every frame type+Two layer type,

(5-2) Voltage read out format+Flush every frame type+Partial read outtype (a single layer, independent signal line)+Spatial correction,

(5-3) Voltage read out format+Flush every frame type+Partial read outtype (a single layer, common signal line)+Spatial correction,

(6-1) Voltage read out format+Flush every frame type+Two layer type+Lowresolution conversion,

(6-2) Voltage read out format+Flush every frame type+Partial read outtype (a single layer, independent signal line)+Spatial correction+Lowresolution conversion,

(6-3) Voltage read out format+Flush every frame type+Partial read outtype (a single layer, common signal line)+Spatial correction+Lowresolution conversion,

(7-1) Voltage read out format+Flush every frame type+Two layer type+Lowresolution conversion of modified algorithm,

(7-2) Voltage read out format+Flush every frame type+Partial read outtype (a single layer, independent signal line)+Spatial correction+Lowresolution conversion of modified algorithm,

(7-3) Voltage read out format+Flush every frame type+Partial read outtype (a single layer, common signal line)+Spatial correction+Lowresolution conversion of modified algorithm,

(8-1) Voltage read out format+Flush every frame type+Partial read outtype (a single layer, independent signal line)+Reuse reconstruction,

(8-2) Voltage read out format+Flush every frame type+Partial read outtype (a single layer, common signal line)+Reuse reconstruction,

(9-1) Voltage read out format+Flush every frame type+Partial read outtype (a single layer, independent signal line)+Reuse reconstruction+Lowresolution conversion,

(9-2) Voltage read out format+Flush every frame type+Partial read outtype (a single layer, common signal line)+Reuse reconstruction+Lowresolution conversion,

(10-1) Voltage read out format+Flush every frame type+Partial read outtype (a single layer, independent signal line)+Reuse reconstruction+Lowresolution conversion of modified algorithm, and

(10-2) Voltage read out format+Flush every frame type+Partial read outtype (a single layer, common signal line)+Reuse reconstruction+Lowresolution conversion of modified algorithm.

The above-mentioned variations are explained below.

(1-1) Electric charge read out format+Two layer type

The electric charge read out format where the electric charge generatedby the irradiated X-rays is read out as a current signal is applied tothe X-ray detectors 12 and 22. In the electric charge read out format,when the data is read out, the electric charge is removed from the pixelcapacitor and the pixel capacitor is reset.

FIG. 8 shows the X-ray detector 12 of the front imaging system. Sincethe X-ray detector 22 of the lateral imaging system is the same as orsimilar to the X-ray detector 12 of the front imaging system, theexplanation for the X-ray detector 22 is omitted.

On a glass substrate 41 of the X-ray detector 12, pixel arrangementlayers 43 and 45 are piled up as two layers. The first layer 45 is ausual TFT structure where a plurality of detection elements 47 arearranged. The second layer 43 is located between the first layer 45 andthe glass substrate 41. Although the number of the detection elements 49(the number of pixels) of the second layer 43 is fewer than the numberof the detection elements 47 of the first layer 45, detection area ofthe detection elements 49 of the second layer is larger than that of thedetection elements 47 of the first layer 45. The detection elements 49of the second layer 43 are arranged in a region that is almost the samesize as the size of the region in which the detection elements 47 of thefirst layer 45 are arranged. The X-rays that penetrate through the firstlayer 45 go into the second layer 43. Since the number of pixels of thesecond layer 43 is fewer than that of the first layer 45, the read outfrom all pixels of the second layer 43 is completed at higher speed(i.e., faster) than that of the first layer 45.

As shown in FIG. 9, the detection area of the detection elements 49 ofthe second layer 43 may be almost the same as the detection area of thedetection elements 47 of the first layer 45, and the detection elements49 may be separately arranged in a region that is almost the same sizeas the region in which the detection elements 47 are arranged.

Alternatively, as shown in FIG. 10, the first layer 45 may be located ona surface of the glass substrate 41, and the second layer 43 may belocated on a back face of the glass substrate 41. Alternatively, asshown in FIG. 11, the first layer 45 may be located on a surface of aglass substrate 41-1, the second layer 43 may be located on a surface ofa glass substrate 41-2, and the substrates may be stacked. In this case,the glass substrate 41-1 may be bonded to the second layer 43, forexample.

FIG. 12 shows an imaging sequence of one cycle in the (electric chargeread out format+Two layer type). In term (1), the X-rays are generatedfrom the F-side X-ray tube 11. In term (1), the direct X-rays from theF-side X-ray tube 11 go through the patient, and are detected as signalcomponents by the first and second layers 45 and 43 of the first ofF-side X-ray detector 12. In term (1), the X-rays from the F-side X-raytube 11 are also scattered inside the patient, and the scattered X-raysare detected as scatter components by the first and second layers of theL-side X-ray detector 22.

In term (2), rough image data S11 is read out from the second layer 43of the F-side X-ray detector 12 at high speed. The image data S11includes the direct X-rays (signal component) from the F-side, which ishereinafter referred to as “FSiR.” In term (2), rough image data S21 isread out from the second layer of the L-side X-ray detector 22 at highspeed in parallel to read out of the rough image data S11 from thesecond layer 43 of the F-side X-ray detector 12. The image data S21mainly includes the scatter component caused by the scattered X-ray fromthe F-side X-ray tube 11, which is hereinafter referred to as “FScR.”After the image data S11 and S21 are read out from the second layers ofthe F-side and L-side X-ray detectors, in term (3), the X-rays aregenerated from the L-side X-ray tube 21. In term (3), the scatteredX-rays among the X-rays from the L-side X-ray tube 21 are detected byfirst and second layers 45 and 43 of the F-side X-ray detector 21. Interm (3), the direct X-rays from the L-side X-ray tube 21 pass throughthe patient and are detected by the first and second layers of theL-side X-ray detector 22.

In term (4), rough image data S12 is read out from the second layer 43of the F-side X-ray detector 12. Since the read electric charge is notheld in the electric charge read out format, the image data S12 read outin term (4) does not reflect the accumulated electric charge in term(1), but mainly indicates the scatter component caused by the X-raysfrom L-side and accumulated in term (3), hereafter “LScR.” Moreover, interm (4), rough image data 22 is read out from the second layer 43 ofthe L-side X-ray detector 22 at high speed in parallel to read out ofthe rough image data S12 from the second layer 43 of the F-side X-raydetector 12. Since the image data S22 read out in term (4) does notreflect the accumulated electric charge in term (1), the image data S22mainly includes the signal component caused by the direct X-rays fromL-side and accumulated in term (3), hereafter “LSiR.”

Furthermore, fine image data S13 is read out from the first layer 45 ofthe F-side X-ray detector 12 at low speed. Since the image data S13 readout from the first layer 45 in term (4) reflects the electric chargeaccumulated in term (1) and term (3), the image data S13 includes thesignal component caused by the direct X-rays from the F-side accumulatedin term (1) and the scatter component caused by the X-rays from theL-side accumulated in term (3), which is referred to as “FSiF+LScF.”Moreover, fine image data S23 is read out from the first layer of theL-side X-ray detector 22 in term (4) at low speed. Since the image dataS23 read out from the first layer in term (4) reflects the electriccharge accumulated in term (1) and term (3), the image data S23 includesthe scatter component caused by the X-rays from the F-side accumulatedin term (1) and the-signal component caused by the direct X-rays fromthe L-side accumulated in term (3), which is referred to as “FScF+LSiF.”With the two layer type, although FIG. 12 shows that the data is readout from the first layer and the second layer in turn in term (4), thedata is read out from the first layer in parallel to the data read outfrom the second layer.

The image processing for the image data obtained by the sequence willnow be explained. Regarding the F-side, since the fine image data S13includes the signal component and the scatter component, it is necessaryto remove the scatter component. The scatter component is included inthe data S12. The scatter component has a lower space frequency thanthat of the signal component, and even low resolution image data can beused. The low resolution image data S12 is converted to such highresolution image data (fine conversion) as the image data S13, and whensubtraction is performed between the converted image data S12 related tothe scatter component and the fine image data S13, L-side fine imagedata where the scatter component is removed can be created.

Similarly, regarding the L-side, the image data S23 obtained in highresolution includes the scatter component caused by the X-rays from theF-side X-ray tube 11. The scatter component is included in the imagedata S21. The image data S21 is converted to high resolution image data,such as the image data S23, and when a subtraction is performed betweenthe converted image data S21 related to the scatter component and thefine image data S23, fine image data S24 where the scatter component isremoved can be created.

As described above, in the embodiment, it is possible to read out thedata from the F-side and the L-side in parallel. Therefore, it ispossible to improve the frame rate in comparison with the serial dataread out from the L-side and the F-side. Moreover, although it is usefulto read out the scatter component to remove the scatter component fromeach image, in the non-limiting embodiment, the influence caused by theread out operation of the scatter component to the cycle time can bereduced by reading out the scatter component at low resolution and athigh speed (short time), considering that spatial frequency of thescatter component is low. Furthermore, by reading out the scattercomponent at low resolution and at high speed, term (2) can be shortenedand a gap for imaging time between the F-side and the L-side can beshortened.

(1-2) Electric charge read out format+Partial read out type (a singlelayer, independent signal line)+Spatial correction

In the two layer type as mentioned above, the second layer where thepixels are arranged roughly is separated from the first layer where thepixels are arranged finely. However, in a partial read out type X-raydetector (a single layer, independent signal line), pixels are arrangedon a single layer. Rough image data is read out from specific pixels interms (2) and (4), and fine image data is read out from the pixels otherthan the specific pixels in term (4).

FIG. 13 shows the partial read out type X-ray detector (a single layer,independent signal line). The specific pixels shown as a double slashare assigned to read out the rough image data, and the other pixels 51shown as a single slash are assigned to read out the fine image data.The number of the specific pixels 52 is fewer than the number of thepixels 51. The specific pixels are separately arranged in a lengthwisedirection and a crosswise direction such that the pixels 51 aretherebetween. The specific pixels 52 in the crosswise direction areconnected to a gate line 54 that can drive the specific pixels 52independently from the pixels 51 driven by a gate line 53. The specificpixels 52 in the lengthwise direction are connected to a signal line 56that is independent from a signal line 55 of the pixels 51. At highspeed read out, the gate lines 54 connected to the specific pixels 52are activated in turn, and the data is read out via the signal lines 56connected to the specific pixels in turn.

In term (2) of FIG. 12, the rough image data S11 is read from thespecific pixel 52 of the F-side X-ray detector 12 at high speed, and (inparallel) the rough image data S21 is read from the specific pixel 52 ofthe L-side X-ray detector 22 at high speed. Also in term (4), the roughimage data S12 is read from the specific pixel 52 of the F-side X-raydetector 12 at high speed, and (in parallel) the rough image data S22 isread from the specific pixel 52 of L-side X-ray detector 22 at highspeed. In the same term (4), the fine image data S13 is read from theother pixels 51 of the F-side X-ray detector 12 at low speed, and inparallel, the fine image data S23 is read from the other pixels 51 ofthe L-side X-ray detector 22 at low speed. Although it is described inFIG. 12 that the data read out from the specific pixels 52 is performedseparately from the data read out from the other pixels 51 in turn,these data read outs are performed in parallel.

Regarding the F-side, the low resolution image data S12 is converted tohigh resolution image data (fine conversion) such as the image data S13to remove the scatter component from the high resolution image data 13.When subtraction is performed between the converted image data S12related to the scatter component and the fine image data S13 includingthe signal component and the scatter component, L-side fine image datawhere the scatter component is removed can be created.

Since the partial pixels are applied to the specific pixels 52, signalsfrom the specific pixels 52 are lacking in the image data S13. Since thepartial pixels are applied to the specific pixels 52 in the independentpartial read out type, signals are lacking that correspond to thespecific pixels on the image data. When the image data S13 where ascatter component is removed by subtraction is spatially corrected, thedata corresponding to the specific pixels is interpolated.

Similarly, regarding the L-side, in order to remove the scattercomponent from the fine image data S23 including the signal componentand the scatter component, the rough image data S21 including thescatter component is converted to high resolution image data such as theimage data S23, the fine converted image data S21 including the scattercomponent is removed from the image data 23 including the signalcomponent and the scatter component. Thereby, the fine image data thatmainly has the signal component is created. When the image data S23where the scatter component is removed by subtraction is spatiallycorrected, the data corresponding to the specific pixels isinterpolated. In this way, the frame rate can be improved, the influencecaused by the read out operation of the scatter component to the cycletime can be reduced, and the gap for imaging time between the F-side andthe L-side can be shortened.

(1-3) Electric charge read out format+Partial read out type (a singlelayer, common signal line)+Spatial correction

As shown in FIG. 14, the signal lines 55 may be commonly used for thespecific pixel and other pixels in the partial read out type. The gateline 54 of the specific pixel 52 is independent from other gate lines 53of other pixels 51. Since the image processing for subtraction is thesame as or similar to what is explained in (1-2), the explanation isomitted. Through this configuration, the frame rate can be improved, theinfluence caused by the read out operation of the scatter component tothe cycle time can be reduced, and the gap for imaging time between theF-side and the L-side can be shortened.

In addition, in type (1-3) as shown in FIG. 15, the specific pixel 52may be adapted per line. Specific gate lines 54 separated in thelengthwise direction by predetermined gate lines 53 are adapted. Severalpixels connected to the specific gate line 54 and located on the sameline are used as the specific pixels when the rough image data is readout. The rough pixel data S11, S12, S21, and S22 are read out when thespecific gate lines 54 are driven in order. The data is read out fromthe all signal lines 55 during the driving of the specific gate lines54. In this type, the conventional composition of the X-ray detector canbe used.

(2-1) Electric charge read out format+Partial read out type (a singlelayer, independent signal line)+Reuse reconstruction

This type is different from (1-2) mainly with respect to the imageprocessing. In (1-2), the data of the specific pixels that cause thesignal lack is interpolated by using the spatial correction. On theother hand, as shown in FIG. 16, the data of the specific pixels thatcause the signal lack in the fine image data S13 and S23 where thescatter component is removed by the subtraction, is interpolated by therough image data S11 that includes the signal component and that is readout from the specific pixels of the F-side X-ray detector 12 in term(2). Regarding the L-side, the rough image data S22 that mainly includesthe signal component and that is read out from the specific pixels 52 ofthe L-side X-ray detector 22 in term (4) is used for the interpolation.Since the image data S11 mainly includes the signal component by thedirect X-rays from the F-side and includes little scatter component, thefine image data mainly including the signal component can be obtained.

(2-2) Electric charge read out format+Partial read out type (a singlelayer, common signal line)+Reuse reconstruction

This type is different from type (1-3) mainly in terms of imageprocessing. In this image processing, the data of the specific pixelsthat cause the signal lack in the fine image data S13 and S23 where thescatter component is removed by subtraction, is interpolated by therough image data S11 that mainly includes the signal component and isread from the specific pixel 52 of the F-side X-ray detector 12 in term(2). Regarding the L-side, the rough image data S22 that mainly includesthe signal component and read out from the specific pixels 52 of theL-side X-ray detector 22 in term (4) is used for the interpolation.

(3-1) Voltage read out format+Flush every read out type+Two layer type

Unlike the electric charge read out format, in the voltage read outformat, an electric charge is held in the pixel capacitor even after theread out. Therefore, after the rough image data S12 is read out from thesecond layer of the F-side X-ray detector 12 in term (2) and before theX-rays are irradiated from the L-side in term (3), as shown in FIG. 17,a flush operation that resets the electric charge of the pixel capacitorof the second layer is performed. By the reset, mixing of the signalcomponent with the image data S12 can be reduced, and the scattercomponent can be enhanced.

Similarly, the flush operation that resets the electric charge of thepixel capacitor of the second layer is performed after the rough imagedata S22 is read out from the second layer of the L-side X-ray detector22 in term (2) and before the X-rays are irradiated from the L-side interm (3). By the reset, mixing of the scatter component with image dataS22 can be reduced, and the signal component can be enhanced. Moreover,after the image data S12 and S13 is read out from the first and secondlayers of the F-side X-ray detector 12 in term (4) and before the X-raysare irradiated from the F-side in the following cycle, the operationthat resets the electric charge of the pixel capacitor of the firstlayer and the second layer is performed. By this reset, the carry-overof the electric charge to the following cycle can be reduced. Similarly,after the image data S22 and S23 is read out from the first and secondlayers of the L-side X-ray detector 22 in term (4) and before the X-raysare irradiated from the L-side in the following cycle, the operationthat resets the electric charge of the pixel capacitor of the firstlayer and the second layer is performed. By this reset, the carry-overof the electric charge to the following cycle can be reduced. The imageprocessing is the same as or similar to (1-1).

(3-2) Voltage read out format+Flush every read out type+Partial read outtype (a single layer, independent signal line)+Spatial correction

Although the flush operation is performed in the above-mentioned voltageread out format, it is similar to a case where the electric charge readout format of (1-2) is changed to the voltage read out format. In thiscase, on the F-side, the pixel capacitor of the specific pixel 52 isreset in term (2) after the read out of the image data S11. All pixelcapacitors including the specific pixel 52 and other pixels 51 are resetafter the read out of the image data S12 and S13 in term (4). Similarly,the pixel capacitor of the specific pixel 52 of the L-side is also resetafter the read out of the image data S21 in the term (2), and all pixelsincluding the specific pixel 52 and other pixels 51 are reset after theread out of the image data S22 and S23 in term (4). The image processingis similar to the image processing of (1-2). On the F-side, the datacorresponding to the specific pixels 52 that cause the signal lack inthe image data S13 where the scatter component is removed bysubtraction, is interpolated using the spatial correction. Similarly, onthe L-side, the data corresponding to the specific pixels 52 that causethe signal lack in the image data S23 where the scatter component isremoved by subtraction, is interpolated using the spatial correction.

(3-3) Voltage read out format+Flush every read out type+Partial read outtype (a single layer, common signal line)+Spatial correction

When the voltage read out format is used instead of the electric chargeread out format of (1-3), since the electric charge is held, the flushis also performed. On the F-side, the pixel capacitors of the specificpixels 52 are reset after the image data S11 is read out in term (2),and the pixel capacitors of all pixels including the specific pixels andthe other pixels are also reset, after the image data S12 and S13 isread out in term (4). On the L-side, the pixel capacitors of thespecific pixels 52 are reset after the image data S21 is read out interm (2), and also the pixel capacitors of all pixels including thespecific pixels and the other pixels are reset, after the image data S22and S23 is read out in term (4).

The image processing is the same as or similar to what is explained in(1-3). Regarding the F-side, the data corresponding to the specificpixels 52 is spatially interpolated. Similarly, regarding the L-side,the data corresponding to the specific pixels is spatially interpolated.

(4-1) Voltage read out format+Flush every read out type+Partial read outtype (a single layer, independent signal line)+Reuse reconstruction

This type is different from (3-2) mainly with respect to the imageprocessing. As shown in FIG. 18, the image processing is performed by areuse reconstruction instead of spatial correction. On the F-side, thedata of the specific pixels that cause the signal lack in the fine imagedata S13 and S23 where the scatter component is removed by subtraction,is interpolated by the rough image data S11 that includes the signalcomponent read out from the specific pixels of the F-side X-ray detector12 in term (2). Regarding the L-side, the rough image data S22 thatmainly includes the signal component read out from the specific pixels52 of the L-side X-ray detector 22 in term (4) is used for theinterpolation.

(4-2) Voltage read out format+Flush every read out type+Partial read outtype (a single layer, common signal line)+Reuse reconstruction

This type is different from (3-3) mainly with regard to the imageprocessing. As shown in FIG. 18, the image processing is performed byreuse reconstruction instead of spatial correction. On the F-side, thedata of the specific pixels that cause the signal lack in the fine imagedata S13 and S23 where the scatter component is removed by subtractionis interpolated by the rough image data S11 that includes the signalcomponent read out from the specific pixels of the F-side X-ray detector12 in term (2). Regarding the L-side, the rough image data S22 thatmainly includes the signal component read out from the specific pixels52 of the L-side X-ray detector 22 in term (4) is used for theinterpolation.

(5-1) Voltage read out format+Flush every frame type+Two layer type

This type is different from (3-1) mainly with respect to the imageprocessing and the timing of the flush operation. The timing of theflush operation is shown in FIG. 19, which shows that the electriccharge of the pixel capacitor of the second layer of the F-side and theL-side X-ray detectors 12 and 22 is not reset in term (2). After theimage data S12 and S13 is read out from the first and second layers ofthe F-side X-ray detector 12 in term (4) and before the X-rays areirradiated from the F-side in the following cycle, the operation thatresets the electric charge of the pixel capacitor of the first layer andthe second layer is performed. Similarly, after the image data S22 andS23 is read out from the first and second layers of the L-side X-raydetector 22 in term (4) and before the X-rays are irradiated from theL-side in the following cycle, the operation that resets the electriccharge of the pixel capacitor of the first layer and the second layer isperformed.

Since the electric charge of the pixel capacitor of the second layer ofthe F-side and the L-side X-ray detectors 12 and 22 in term (2), therough image data S12 and S22 read out in term (4) includes the signalcomponent and the scatter component. To remove the signal component fromthe image data S12 to obtain the scatter component, the image data S11mainly including the signal component is subtracted from the image dataS12 including both the signal component and the scatter component. Thefine image data that is converted from the image data S12 mainlyincluding the scatter component is subtracted from the fine image dataS13 including both the signal component and the scatter component toobtain the fine image data that includes almost none of the scattercomponent. The image processing for the L-side is the same as or similarto (3-1).

(5-2) Voltage read out format+Flush every frame type+Partial read outtype (a single layer, independent signal line)+Spatial correction

This type is different from (3-2) mainly with regard to image processingand timing of the flush operation. As flush shown in FIG. 19, theelectric charge of the pixel capacitor of the second layer of the F-sideand L-side X-ray detectors 12 and 22 is not reset in term (2). To removethe signal component from the image data S12 and to obtain the scattercomponent, the image data S11 mainly including the signal component issubtracted from the image data S12 including both the signal componentand the scatter component. The fine image data that is converted fromthe image data S12 mainly including the scatter component is subtractedfrom the fine image data S13 including both the signal component and thescatter component to obtain the fine image data that includes almostnone of the scatter component. When the spatial correction is performedto the fine image data S13 that does not include the scatter component,the data corresponding to the specific pixel is interpolated. The imageprocessing for the L-side is the same as or similar to (3-2).

(5-3) Voltage read out format+Flush every frame type+Partial read outtype (a single layer, common signal line)+Spatial correction

This type is different from (3-3) mainly with respect to imageprocessing and timing of the flush operation. As flush shown in FIG. 19,the electric charge of the pixel capacitor of the second layer of theF-side and L-side X-ray detectors 12 and 22 is not reset in term (2). Toremove the signal component from the image data S12 and to obtain thescatter component, the image data S11 mainly including the signalcomponent is subtracted from the image data S12 including both thesignal component and the scatter component. The fine image data that isconverted from the image data S12 mainly including the scatter componentis subtracted from the fine image data S13 including both the signalcomponent and the scatter component to obtain the fine image data thatincludes almost none of the scatter component. When the spatialcorrection is performed to the fine image data S13 that does not includethe scatter component, the data corresponding to the specific pixel isinterpolated. The image processing to the L-side is the same as orsimilar to (3-3).

(6-1) Voltage read out format+Flush every frame type+Two layer type+Lowresolution conversion

This type is different from (5-1) mainly with regard to the imageprocessing. In (5-1), when the image data S11 mainly including thesignal component is subtracted from the image data S12 including thesignal component and the scatter component, the image data that mainlyincludes the scatter component but includes almost none of the signalcomponent is created. On the other hand, in (6-1), the resolution of theimage data S13 including the signal component and the scatter componentis reduced (by low resolution conversion) as much as the rough imagedata S11 by a pixel skipping calculation or a local average calculation.When the rough image data mainly including the signal component issubtracted from the rough image data converted by low resolutionconversion, the rough image data 13 mainly including the scattercomponent is created. The rough image data 13 is converted to the fineimage data, and the fine image data 13 is subtracted from the fine imagedata. Thereby, the fine image data that includes almost none of thescatter component is created. The image processing for the L-side is thesame as or similar to (5-1).

(6-2) Voltage read out format+Flush every frame type+Partial read outtype (a single layer, independent signal line)+Spatial correction+Lowresolution conversion

This type is different from the type of the above (5-2) mainly regardingimage processing. In (6-2) as well as in (6-1), the resolution of theimage data S13 including the signal component and the scatter componentis reduced as much as the rough image data S11 by a pixel skippingcalculation or a local average calculation. When the rough image datamainly including the signal component is subtracted from the rough imagedata converted by low resolution conversion, the rough image data S13mainly including the scatter component is created. The rough image dataS13 mainly including the scatter component is converted to the fineimage data S13, and the fine image data S13 is subtracted from thenon-converted original fine image data S13. Thereby, the fine image dataS13 that does not almost include the scatter component is created. Theimage processing for the L-side is the same as or similar to the (5-2).

(6-3) Voltage read out format+Flush every frame type+Partial read outtype (a single layer, common signal line)+Spatial correction+Lowresolution conversion

This type is different from (5-3) mainly with regard to the imageprocessing. In (6-3) as well as (6-1), the resolution of the image dataS13 including the signal component and the scatter component is reducedas much as the rough image data S11 by a pixel skipping calculation or alocal average calculation. When the rough image data S11 mainlyincluding the signal component is subtracted from the rough image dataS13 converted by low resolution conversion, the rough image data S13mainly including the scatter component is created. The rough image dataS13 is converted to the fine image, and the fine image data S13 issubtracted from the fine image data S13. Thereby, the fine image dataS13 that includes almost none of the scatter component is created. Theimage processing to the L-side is the same as or similar to the (5-3).

(7-1) Voltage read out format+Flush every frame type+Two layer type+Lowresolution conversion of modified algorithm

This type is different from (6-1) mainly with respect to the algorithmof the low resolution conversion. In (7-1), the rough image data S11mainly including the signal component is converted to the fine imagedata, and the fine image data is subtracted from the fine image data S13including both the signal image data and the scatter data. The fineimage data S13 mainly including the scatter component is created, andthe fine image data S13 mainly including the scatter component issubtracted from the fine image data S13.

(7-2) Voltage read out format+Flush every frame type+Partial read outtype (a single layer, independent signal line)+Spatial correction+Lowresolution conversion of modified algorithm

This type is different from (6-2) mainly with respect to the algorithmfor low resolution conversion. The order between the fine conversion andthe subtraction is reversed in comparison with (6-2). In (7-2), afterthe rough image data S11 mainly including the signal component isconverted to the fine image data, the converted image data is subtractedfrom the fine image data S13 including the signal component and thescatter component. Thereby, the created fine image data S13 mainlyincluding the scatter component is subtracted from the fine image dataS13.

(7-3) Voltage read out format+Flush every frame type+Partial read outtype (a single layer, common signal line)+Spatial correction+Lowresolution conversion of modified algorithm

This type is different from (6-3) mainly regarding low resolutionconversion algorithm. The order between the fine conversion and thesubtraction is reversed in comparison with (6-3). In (7-3), after therough image data S11 mainly including the signal component is convertedto the fine image, the converted image data is subtracted from the fineimage data S13 including the signal component and the scatter component.Thereby, the created fine image data S13 mainly including the scattercomponent is subtracted from the fine image data S13.

(8-1) Voltage read out format+Flush every frame type+Partial read outtype (a single layer, independent signal line)+Reuse reconstruction

This type uses the reuse reconstruction instead of the spatialcorrection used in (5-2). In (5-2), the spatial correction is performedto the image data S13 that includes almost none of the scatter componentby subtraction, and the data corresponding to the specific pixels isinterpolated. In (8-1), the data corresponding to the specific pixels onthe image data S13 that includes almost none of the scatter component isinterpolated by the rough image data S11 that mainly includes the signalcomponent that is read out in term (2).

Regarding the L-side, the rough image data S21 that mainly includes thescatter component read out in term (2) is subtracted from the roughimage data S22 that includes the signal component and the scattercomponent that is read out in term (4). Thereby, the rough image datafor interpolation mainly including the signal component is created. Byusing the created imaged data mainly including the signal component, thedata corresponding to the specific pixels on the fine image data S23that includes almost none of the scatter component is interpolated.

(8-2) Voltage read out format+Flush every frame type+Partial read outtype (a single layer, common signal line)+Reuse reconstruction

In this type, reuse reconstruction is used instead of spatialcorrection, which is different from (5-3). In (5-3), the lacked datacorresponding to the specific pixel is interpolated with the spatialcorrection of the fine image data that includes almost none of thescatter component and that is created by subtraction. In (8-2), the datacorresponding to the specific pixels on the image data S13 that includesalmost none of the scatter component and that is created by subtractionis interpolated by the image data S11 that mainly includes signalcomponent read out in term (2).

Regarding the L-side, the rough image data S21 that mainly includes thescatter component read out in term (2) is subtracted from the roughimage data S22 that includes the signal component and the scattercomponent read out in term (4). Thereby, the rough image data forinterpolation mainly including the signal component is created. By usingthe created imaged data mainly including the signal component, the datacorresponding to the specific pixels on the fine image data S23 thatincludes almost none of the scatter component is interpolated.

(9-1) Voltage read out format+Flush every frame type+Partial read outtype (a single layer, independent signal line)+Reuse reconstruction+Lowresolution conversion

This type is different from (8-1) mainly about the following point. In(8-1), to create the fine image data mainly including the scattercomponent to be subtracted from the fine image data S13 including thesignal component and the scatter component, the rough image data mainlyincluding the scatter component is created by subtracting the roughimage data S11 mainly including the signal component in term (2) fromthe rough image data S12 including the signal component and the scattercomponent in term (4). In (9-1), the fine image data S13 including thesignal component and the scatter component in term (4) is converted torough image data S13 by low resolution conversion, and the rough imagedata S11 mainly including the signal component in term (2) is subtractedfrom the created rough image data S13 by conversion. Thereby, the fineimage data is created mainly including the scatter component to besubtracted from the fine image data S13 including the signal componentand the scatter component.

Similarly, regarding the L-side, the fine image data S23 including thesignal component and the scatter component in term (4) is converted torough image data by low resolution conversion, and the rough image dataS21 mainly including the signal component in term (2) is subtracted fromthe rough image data S23. Thereby, the fine image data is created mainlyincluding the scatter component to be subtracted from the fine imagedata S23 including the signal component and the scatter component.

(9-2) Voltage read out format+Flush every frame type+Partial read outtype (a single layer, common signal line)+Reuse reconstruction+Lowresolution conversion

This type is different from (8-2) mainly about the following point. In(8-2), to create the fine image data mainly including the scattercomponent to be subtracted from the fine image data S13 including thesignal component and the scatter component, the rough image data mainlyincluding the scatter component is created by subtracting the roughimage data S11 mainly including the signal component in term (2) fromthe rough image data S12 including the signal component and the scattercomponent in term (4). In (9-2), the fine image data S13 including thesignal component and the scatter component in term (4) is converted torough image data by low resolution conversion, and the rough image dataS11 mainly including the signal component in term (2) is subtracted fromthe rough image data S13. Thereby, fine image data is created mainlyincluding the scatter component to be subtracted from the fine imagedata S13 including the signal component and the scatter component.

Similarly, regarding the L-side, the fine image data S23 including thesignal component and the scatter component in term (4) is converted torough image data by low resolution conversion, and the rough image dataS21 mainly including the signal component in term (2) is subtracted fromthe rough image data S23. Thereby, the fine image data is created mainlyincluding the scatter component to be subtracted from the fine imagedata S23 including the signal component and the scatter component.

(10-1) Voltage read out format+Flush every frame type+Partial read outtype (a single layer, independent signal line)+Reuse reconstruction+Lowresolution conversion of modified algorithm

In (9-1), the fine image data S13 including the signal component and thescatter component in term (4) is converted to rough image data by lowresolution conversion, and the rough image data S11 mainly including thesignal component in term (2) is subtracted from the created rough imagedata S13 by conversion. Thereby, fine image data is created mainlyincluding the scatter component to be subtracted from the fine imagedata S13 including the signal component and the scatter component. In(10-1), the rough image data S11 mainly including the signal componentin term (2) is converted to fine image data, and the created fine imagedata mainly including the signal component is subtracted from the fineimage data S13 including the signal component and the scatter componentin term (4). Thereby, the fine image data mainly including the scattercomponent to be subtracted from the fine image data S13 including thesignal component and the scatter component is created.

Similarly, regarding the L-side, the rough image data S21 mainlyincluding the signal component in term (2) is converted to fine imagedata, and the created fine image data mainly including the signalcomponent is subtracted from the fine image data S23 including thesignal component and the scatter component in term (4). Thereby, thefine image data mainly including the scatter component to be subtractedfrom the fine image data including the signal component and the scattercomponent in term (4).

(10-2) Voltage read out format+Flush every frame type+Partial read outtype (a single layer, common signal line)+Reuse reconstruction+Lowresolution conversion of modified algorithm

This type is different from (9-2) mainly about the following point. In(9-2), the fine image data S13 including the signal component and thescatter component in term (4) is converted to rough image data by lowresolution conversion, and the rough image data S11 mainly including thesignal component in term (2) is subtracted from the rough image dataS13. Thereby, fine image data is created mainly including the scattercomponent to be subtracted from the fine image data S13 including thesignal component and the scatter component.

By contrast, in (10-2), the rough image data S11 mainly including thesignal component in term (2) is converted to the fine image, and thefine image data is subtracted from the fine image data S13 including thesignal component and the scatter component in term (4). Thereby, thefine image data mainly including the scatter component is to besubtracted from the fine image data S13 including the signal componentand the scatter component in term (4).

Similarly, regarding the L-side, the rough image data S21 mainlyincluding the signal component in term (2) is converted to fine imagedata, and the fine image data is subtracted from the fine image data S23including the signal component and the scatter component in term (4).Thereby, the fine image data mainly including the scatter component isto be subtracted from the fine image data S23 including the signalcomponent and the scatter component in term (4).

In at least one of the above embodiments of the X-ray diagnosisapparatus for obtaining at least two X-ray images from respectivedirections, the influence of the scatter X-rays is reduced or the framerate is improved.

The present invention may be not limited to the above embodiments, andvarious modifications may be made without departing from the spirit orscope of the general inventive concept. It is therefore to be understoodthat within the scope of the appended claims, the present invention maybe practiced differently than as specifically described herein. Althoughthe above embodiment and modification may include various steps orvarious elements, one or more steps or elements may be arbitrarilyselected. For instance, one or more steps or elements described as theembodiment or modification may be omitted.

For example, the X-ray detector may be a direct change type X-raydetector that directly changes an incident X-rays into an electriccharge, or an indirect change type that changes an incident X-rays intoan optical signal and changes the optical signal to an electric charge.In the above, it is explained that a solid flat detector that includesTFT is used as the X-ray detectors, however other detector, such as asemiconductor-type detector or a gas-type detector may be used. One ofsemiconductor-type detectors includes arranged detection elements usingFET and Si, for example. One of gas-type detectors uses a gas that islocated in a sealed box, such as an ionization chamber, in order tochange X-rays to electric charges.

1-4. (canceled)
 5. An X-ray diagnosis apparatus, comprising: a pluralityof X-ray tubes; and a plurality of X-ray detectors corresponding torespective X-ray tubes, wherein each of the plurality of X-ray detectorsincludes a first image data collection function for collecting imagedata using a first number of detection elements and a second image datacollection function for collecting image data by a second number ofdetection elements, the second number being fewer than the first number.6. The X-ray diagnosis apparatus according to claim 5, wherein adistribution range of the detection elements in the second image datacollection function is substantially identical to a distribution rangeof the detection elements in the first data collection function.
 7. TheX-ray diagnosis apparatus according to claim 5, wherein the X-raydetector comprises: a first detection part for collecting the firstimage data; and a second detection part for collecting the second imagedata.
 8. The X-ray diagnosis apparatus according to claim 7, wherein arange of detection of the second detection part is substantiallyidentical to a range of detection of the first detection part.
 9. TheX-ray diagnosis apparatus according to claim 5, wherein the X-raydetector further comprises a switch configured to switch between thefirst image data collection function and the second image datacollection function. 10-23. (canceled)